Dometic RM2454 Heat Pump User Manual


 
8
ELECTRICAL CONNECTION
120 Volts AC Connection
The refrigerator is equipped with a three-prong (ground-
ing) plug for your protection against shock hazards and
should be plugged directly into a properly grounded
three-prong receptacle. DO NOT cut or remove the
grounding prong from this plug. The free length of the
cord is 2 feet and therefore recommended that the re-
ceptacle be located to the left side of the refrigerator
(viewed from the rear) and approximately 6 inches from
the floor (see FIG. 11). This allows easy access through
the vent door. The cord should be routed to avoid direct
contact with the burner cover, flue cover or any other
components that could damage the cord insulation.
12 Volts DC Connection
This refrigerator model require a continuous 12 volt DC
supply to maintain the automatic energy system.
The connection is made to the positive (+) and negative
(-) terminals of the terminal block on back of the refrig-
erator. (See FIG. 1). Correct polarity must be observed
when connecting to the DC supply.
DO NOT use the chassis or vehicle frame as one of the
conductors. Connect two wires at the refrigerator and
route to the DC supply.
The distance the current must travel from the battery to
the refrigerator dictates the AWG wire size to be used.
Should the wire be too small for the distance, a voltage
drop will result.
The voltage drop affects the wattage output of the 12 volt
cartridge heater and resultant refrigerator performance.
The 12 volt DC heater is fused with a 30 amp. in-line blade
fuse.
Recommended wire sizes are shown below.
OPERATING
INSTRUCTIONS
IMPORTANCE OF LEVELING A
REFRIGERATOR
In an absorption refrigerator system, ammonia is lique-
fied in the finned condenser coil at the top rear of the
refrigerator. The liquid ammonia then flows into the
evaporator (inside the freezer section) and is exposed
to a circulating flow of hydrogen gas, which causes the
ammonia to evaporate, creating a cold condition in the
freezer.
When starting this refrigerator for the very first time, the
cooling cycle may require up to four hours of running
time before the cooling unit is fully operational.
The tubing in the evaporator section is specifically sloped
to provide a continuous movement of liquid ammonia,
flowing downward by gravity through this section. If the
refrigerator is operated when it is not level and the ve-
hicle is not moving, liquid ammonia will accumulate in
sections of the evaporator tubing. This will slow the cir-
culation of hydrogen and ammonia gas, or in severe
cases, completely block it, resulting in a loss of cooling.
Any time the vehicle is parked for several hours with the
refrigerator operating, the vehicle should be leveled to
prevent this loss of cooling.
The vehicle needs to be leveled only so it is comfortable
to live in (no noticeable sloping of floor or walls).
When the vehicle is moving, the leveling is not critical,
as the rolling and pitching movement of the vehicle will
pass to either side of level, keeping the liquid ammonia
from accumulating in the evaporator tubing.
OPERATION
Before starting the refrigerator, check that all the manual
gas valves are in the ON position. DO NOT forget the
manual shutoff valve on the rear of the refrigerator see
FIG. 1.
This refrigerator is equipped with a semi Automatic
Energy Selector (AMES) control system, which can be
set to automatically select either 120 volt AC or LP gas
operation (AUTO mode), or if desired LP gas only (GAS
mode). On 3-way model the control system can manu-
ally be set to DC operation (DC mode).
The refrigerator controls will work down to 9.6 volt DC.
Most LP gas appliances used in recreational ve-
hicles are vented to the outside of the vehicle.
When parked close to a gasoline pump, it is pos-
sible that the gasoline fumes could enter this
type of appliance and ignite from the burner
flame, CAUSING A FIRE OR AN EXPLOSION.
FOR YOUR SAFETY, when refueling, shut off all
LP gas appliances which are vented to the out-
side.
! WARNING
6”
120 Volt AC
receptacle
FIG. 11
The wires from the battery to the refrigerator must be of
large enough size to handle the load. The connections
must be clean, tight and free from corrosion. If not, a
resulting voltage drop will cause a decreased cooling
capacity.
MAXIMUM TOTAL CONDUCTOR WIRE LENGTH
(In feet and meters)
RM 2454
Wire length AWG
17 ft.
10
5 m
27 ft.
8
8 m